Prospective study of dietary acrylamide and risk of colorectal cancer among women.

There has been considerable discourse about whether exposure to acrylamide in foods could increase the risk of human cancer. Acrylamide is classified as a probable human carcinogen, and animal studies have demonstrated an increased incidence of tumors in rats exposed to very high levels. Still, epidemiologic data of the effect of dietary acrylamide remain scant. We have undertaken the first prospective study of acrylamide in food and risk of colon and rectal cancers using prospective data from the Swedish Mammography Cohort. The cohort comprised 61,467 women at baseline between 1987 and 1990. Through 2003, the cohort contributed 823,072 person-years, and 504 cases of colon and 237 of rectal cancer occurred. Mean intake of acrylamide through diet was 24.6 mug/day (Q25-70 = 18.7-29.9). Coffee (44%), fried potato products (16%), crisp bread (15%) and other breads (12%) were the greatest contributors. After adjusting for potential confounders, there was no association between estimated acrylamide intake and colorectal cancer. Comparing extreme quintiles, the adjusted relative risks (95% CI; p for trend) were for colorectal cancer 0.9 (0.7-1.3; p = 0.80), colon cancer 0.9 (0.6-1.4; p = 0.83) and rectal cancer 1.0 (0.6-1.8; p = 0.77). Furthermore, intake of specific food items with elevated acrylamide (e.g., coffee, crisp bread and fried potato products) was not associated with cancer risk. In this large prospective study, we found no evidence that dietary intake of acrylamide is associated with cancers of the colon or rectum. Epidemiologic studies play an important role in assessing the possible health effects of acrylamide intake through food. Copyright 2005 Wiley-Liss, Inc.